Morphology is the study of words, word formation, and the relationship between words. In Morphology, we look at morphemes - the smallest lexical items of meaning. Studying morphemes helps us to understand the meaning, structure, and etymology (history) of words.
Morphemes: meaning
The word morphemes from the Greek morphḗ, meaning 'shape, form'. Morphemes are the smallest lexical items of meaning or grammatical function that a word can be broken down to. Morphemes are usually, but not always, words.
Look at the following examples of morphemes:
These words cannot be made shorter than they already are or they would stop being words or lose their meaning.
For example, 'house' cannot be split into ho- and -us' as they are both meaningless.
However, not all morphemes are words.
For example, 's' is not a word, but it is a morpheme; 's' shows plurality and means 'more than one'.
The word 'books' is made up of two morphemes: book + s.
Morphemes play a fundamental role in the structure and meaning of language, and understanding them can help us to better understand the words we use and the rules that govern their use.
How to identify a morpheme
You can identify morphemes by seeing if the word or letters in question meet the following criteria:
Types of morphemes
There are two types of morphemes: free morphemes and bound morphemes.
Free morphemes
Free morphemes can stand alone and don't need to be attached to any other morphemes to get their meaning. Most words are free morphemes, such as the above-mentioned words house, book, bed, light, world, people, and so on.
Bound morphemes
Bound morphemes, however, cannot stand alone. The most common example of bound morphemes are suffixes, such as -s, -er, -ing, and -est.
Let's look at some examples of free and bound morphemes:
'Tall' and 'Tree' are free morphemes.
We understand what 'tall' and 'tree' mean; they don't require extra add-ons. We can use them to create a simple sentence like 'That tree is tall.'
On the other hand, '-er' and '-s' are bound morphemes. You won't see them on their own because they are suffixes that add meaning to the words they are attached to.
Fig. 1 - These are the differences between free vs bound morphemes
So if we add '-er' to 'tall' we get the comparative form 'taller', while 'tree' plus '-s' becomes plural: 'trees'.
Morphemes: structure
Morphemes are made up of two separate classes.
A morpheme's base is the main root that gives the word its meaning.
On the other hand, an affix is a morpheme we can add that changes or modifies the meaning of the base.
'Kind' is the free base morpheme in the word 'kindly'. (kind + -ly)
'-less' is a bound morpheme in the word 'careless'. (Care + -less)
Morphemes: affixes
Affixes are bound morphemes that occur before or after a base word. They are made up of suffixes and prefixes.
Suffixes are attached to the end of the base or root word. Some of the most common suffixes include -er, -or, -ly, -ism, and -less.
Taller
Thinner
Comfortably
Absurdism
Ageism
Aimless
Fearless
Prefixes come before the base word. Typical prefixes include ante-, pre-, un-, and dis-.
Antedate
Prehistoric
Unkind
Disappear
Derivational affixes
Derivational affixes are used to change the meaning of a word by building on its base. For instance, by adding the prefix 'un-' to the word 'kind', we got a new word with a whole new meaning. In fact, 'unkind' has the exact opposite meaning of 'kind'!
Another example is adding the suffix '-or' to the word 'act' to create 'actor'. The word 'act' is a verb, whereas 'actor' is a noun.
Inflectional affixes
Inflectional affixes only modify the meaning of words instead of changing them. This means they modify the words by making them plural, comparative or superlative, or by changing the verb tense.
books - books
short - shorter
quick - quickest
walk - walked
climb - climbing
There are many derivational affixes in English, but only eight inflectional affixes and these are all suffixes.
Word class | Modification reason | Suffixes |
| To modify nouns | Plural & possessive forms | -s (or -es), -'s (or s') |
| To modify adjectives | Comparative & superlative forms | -er, -est |
| To modify verbs | 3rd person singular, past tense, present & past participles | -s, -ed, -ing, -en |
All prefixes in English are derivational. However, suffixes may be either derivational or inflectional.
Morphemes: categories
The free morphemes we looked at earlier (such as tree, book, and tall) fall into two categories:
- Lexical morphemes
- Functional morphemes
Reminder: Most words are free morphemes because they have meaning on their own, such as house, book, bed, light, world, people etc.
Lexical morphemes
Lexical morphemes are words that give us the main meaning of a sentence, text or conversation. These words can be nouns, adjectives and verbs. Examples of lexical morphemes include:
- house
- book
- tree
- panther
- loud
- quiet
- big
- orange
- blue
- open
- run
- talk
Because we can add new lexical morphemes to a language (new words get added to the dictionary each year!), they are considered an 'open' class of words.
Functional morphemes
Functional (or grammatical) morphemes are mostly words that have a functional purpose, such as linking or referencing lexical words. Functional morphemes include prepositions, conjunctions, articles and pronouns. Examples of functional morphemes include:
- and
- but
- when
- because
- on
- near
- above
- in
- the
- that
- it
- them.
We can rarely add new functional morphemes to the language, so we call this a 'closed' class of words.
Allomorphs
Allomorphs are a variant of morphemes. An allomorph is a unit of meaning that can change its sound and spelling but doesn't change its meaning and function.
In English, the indefinite article morpheme has two allomorphs. Its two forms are 'a' and 'an'. If the indefinite article precedes a word beginning with a constant sound it is 'a', and if it precedes a word beginning with a vowel sound, it is 'an'.
Past Tense allomorphs
In English, regular verbs use the past tense morpheme -ed; this shows us that the verb happened in the past. The pronunciation of this morpheme changes its sound according to the last consonant of the verb but always keeps its past tense function. This is an example of an allomorph.
Consider regular verbs ending in t or d, like 'rent' or 'add'.
Now look at their past forms: 'rented' and 'added'. Try pronouncing them. Notice how the -ed at the end changes to an /id/ sound (e.g. rent /ɪd/, add /ɪd/).
Now consider the past simple forms of want, rest, print, and plant. When we pronounce them, we get: wanted (want /ɪd/), rested (rest /ɪd/), printed (print /ɪd/), planted (plant /ɪd/).
Now look at other regular verbs ending in the following 'voiceless' phonemes: /p/, /k/, /s/, /h/, /ch/, /sh/, /f/, /x/. Try pronouncing the past form and notice how the allomorph '-ed' at the end changes to a /t/ sound. For example, dropped, pressed, laughed, and washed.
Plural allomorphs
Typically we add 's' or 'es' to most nouns in English when we want to create the plural form. The plural forms 's' or 'es' remain the same and have the same function, but their sound changes depending on the form of the noun. The plural morpheme has three allomorphs: [s], [z], and [ɨz].
When a noun ends in a voiceless consonant (i.e. ch, f, k, p, s, sh, t, th), the plural allomorph is /s/.
Book becomes books (pronounced book/s/)
When a noun ends in a voiced phoneme (i.e. b, l, r, j, d, v, m, n, g, w, z, a, e, i, o, u) the plural form remains 's' or 'es' but the allomorph sound changes to /z/.
Key becomes keys (pronounced key/z/)
Bee becomes bees (pronounced bee/z/)
When a noun ends in a sibilant (i.e. s, ss, z), the sound of the allomorph sound becomes /iz/.
Bus becomes buses (bus/iz/)
house becomes houses (hous/iz/)
A sibilant is a phonetic sound that makes a hissing sound, e.g. 's' or 'z'.
Zero (bound) morphemes
The zero bound morpheme has no phonetic form and is also referred to as an invisible affix, null morpheme, or ghost morpheme.
A zero morpheme is when a word changes its meaning but does not change its form.
In English, certain nouns and verbs do not change their appearance even when they change number or tense.
Sheep, deer, and fish, keep the same form whether they are used as singular or plural.
Some verbs like hit, cut, and cost remains the same in their present and past forms.
Morphemes - Key takeaways
- Morphemes are the smallest lexical unit of meaning. Most words are free morphemes, and most affixes are bound morphemes.
- There are two types of morphemes: free morphemes and bound morphemes.
- Free morphemes can stand alone, whereas bound morphemes must be attached to another morpheme to get their meaning.
- Morphemes are made up of two separate classes called bases (or roots) and affixes.
- Free morphemes fall into two categories; lexical and functional. Lexical morphemes are words that give us the main meaning of a sentence, and functional morphemes have a grammatical purpose.
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